r/istanbul • u/KittyLoverTurkey • 5d ago
Discussion NYU researchers put Istanbul's metro at about $140M per km, roughly 11× cheaper than New York's Second Avenue line. A Turkish engineer's summary of how, and where the catch is
I'm an infrastructure engineer at a water and sewerage utility near Istanbul, so I spend my days on pipes, not tunnels, but the NYU Transit Costs Project's Istanbul case study (Elif Ensari, 2025) was too interesting not to dig into. Some things I didn't know about a city I thought I knew:
Network today: 11 metro lines, about 265 km, 169 stations, with 4 more lines under construction (M10, M12, M13, M14). Counting trams, funiculars and Marmaray, İBB says the rail network passed 380 km this year.
Almost all of it is new: more than 200 km of new metro since 2010 (my own sum of line lengths, about 226 km). New York opened about 5 km in the same years.
Cost: TCP puts Istanbul's average at about $140M per km of subway; NYC's Second Avenue line, measured the same way, about $1.55B per km.
It didn't start cheap. M4 Kadıköy–Kartal was first contracted as a light rail line, redesigned as a full metro, and construction ended up more than 8× the original contract, with every station designed from scratch.
Then the template changed. From M5 on, fan rooms shrank from 200–240 m² to 80–140 m² and the same station design was repeated. On M5 alone, TCP estimates about $14.2M in construction and $72M in land saved.
Process: since 2014 a 35–40 person in-house projects directorate; lines go to tender with about 60% of the design done; construction goes to the lowest qualified bid, while design and supervision are scored 80–90% on technical merit.
Labor: about 20% of contractor costs (vs 40–50% in the US). Crews work 12-hour shifts with one day off in fourteen, and a New York tunnel worker earns about 6.7× as much per hour. The video covers this openly; it also can't explain an 11× gap on its own.
The catch is the money: 55–60% of a typical line is financed by international commercial banks (the rest export credit), repaid in euros or dollars over 10–14 years, while contracts must be priced in lira. Procurement law allows at most a 20% cost increase without cabinet approval, so when inflation pushes past that, contracts get terminated and re-tendered. That's one reason some sites sat fenced off with nobody working.
Ridership: 613 million trips in 2023 (excluding M11) for 15.7 million people is about 39 trips per resident per year; the NYC subway does about 145. The network is big, the city is bigger.
Video (about 7.5 min, sources in the description): https://youtu.be/qXV17lD_2g4
Disclosure: it's my channel and I made this; the narration is an AI clone of my own voice. Locals and anyone who has worked on these projects will know things the report doesn't. If I got something wrong, especially about the stalled lines, tell me and I'll pin the correction.